A quick vitamin D primer
You walk in the sunshine every day (wearing your SPF, of course). You eat right. You get enough sleep. But you still may be missing something even if you’re doing all the right things—vitamin D. Though rare, severely low levels of vitamin D can cause rickets in children and osteomalacia (softening of the bones) in adults. Left untreated, these conditions can lead to bone pain, and thin, brittle, or misshapen bones, according to the National Institutes of Health. But recent research has suggested a connection between even moderately low levels of vitamin D and a number of surprising health conditions, including diabetes, osteoarthritis, and cancer. There are a number of sneaky signs that can point to a vitamin D deficiency, so if you’re suffering from any of them, talk with your healthcare provider, who will likely recommend a blood test. This is really the only way to accurately determine your vitamin D level. Then you can discuss ways to boost them, usually by taking an over-the-counter supplement.
You’re tired all the time
If you aren’t getting enough vitamin D, you may feel completely exhausted, even if you get plenty of sleep. “There is mounting evidence that vitamin D deficiencies are associated with fatigue and sleep disorders,” says Catherine G. R. Jackson, PhD, a professor of kinesiology and exercise science at California State University in Fresno. A study in the North American Journal of Medical Sciences found that people who felt tired had low levels of vitamin D, but raising their vitamin D to normal levels significantly reduced feelings of fatigue. Not the problem for you? You may have one of these other 13 medical conditions for feeling tired all the time.
Having the blues may be linked to an insufficient amount of vitamin D. According to the Vitamin D Council, vitamin D receptors have been found in many parts of the brain, including in areas linked to depression. Results from studies have been mixed—some researchers have found significant improvements in mood after supplementing with D, while others have not—but that could depend on the severity of the depression as well as the vitamin D deficiency. For example, researchers from Columbia University found that taking vitamin D supplements was effective for those who sufferred from clinically significant depression.